Damages related to strokes of lightning can lead to destruction of vital parts of at wind turbine both in large parts as e.g. blades but also in smaller electronic parts. This destruction of parts in a wind turbine can result in elevated costs throughout the lifetime of the wind turbine because of expensive maintenance of the wind turbine and loss in production of electricity.
One example of damage caused by strokes of lightning in wind turbines using receptors to receive lightning is cracks in the blade of the wind turbine around the part of the receptor which receives the energy (electric current, voltage, charge, etc.) from lightning. Another example of damage invoked may be deterioration of the receptors.
When lightning strikes in a wind turbine, current from lightning can be received by one or more receptors located on the surface of the wind turbine blade. The receptor is part of the surface of the wind turbine blade and the receptor is being destroyed bit by bit from each lightning the receptor receives. Because the receptor is part of the surface of the wind turbine blade, the missing part of the receptor can lead to cracks in the wind turbine blades.
A problem of state-of-the-art wind turbines is that the above-mentioned damages must be checked manually. This manual inspection of e.g. receptors in the surface of a blade has a tendency to be inaccurate e.g. because it is done by means of binoculars and furthermore the manual inspection is costly. Especially it raises the service cost on wind turbines located in areas with relatively many strokes of lightning as e.g. around the equator, where manual inspection of the receptors can be necessary. Moreover, as indicated above, such inspections may not necessarily result in the discovering of all faults on e.g. receptors.